Mitchell had been convicted in January on six criminal counts, including conspiracy to distribute heroin and conspiracy to obstruct justice through murder.

The trafficking operation used female couriers to transport drugs to New Orleans. Polite said a woman charged in the case, Cristina S. Williams, was murdered in Los Angeles in July 2010.

Polite, in a news release about the sentence, praised the work of the Drug Enforcement Administration and Los Angeles Police detectives in the investigation.

“Quenshey Mitchell was willing to do anything to protect his heroin trafficking enterprise, including taking the life of a potential witness against him,” Polite said. “Today’s sentence ensures that his drug dealing and violence will come to an end, as he will spend the rest of his life behind bars.”